nwg - standard network working group module

       nwg - standard network working group module

       The  Standard Network Working Group module is an original implemtation of the recommendations proposed by
       the NWG and currently found in the form of Request for Comments (RFC). Most of the objects are used  with
       networking application, with the most common one beeing the Universal Resource Identifier (URI) object.

       Theuriclass
       The  Uri  class  is  a  base  class  that parses a Uniform Resource Identifier or uri string and provides
       methods to access individual component of that uri. The implementation conforms  to  RFC  3986.  The  URI
       components are the scheme, the authority, the path, the query and the fragment. The class also takes care
       of the character escaping.

       const uri (afnix:www:Uri "http://www.afnix.org")

       An  uri  can be broken into several components called the scheme, the authority, the path, optionally the
       query and the fragment. The Uri class provide a method to retrieve each component of the parsed uri.

       const uri (afnix:www:Uri "http://www.afnix.org/")
       println (uri:get-scheme)    # http
       println (uri:get-authority) # www.afnix.org
       println (uri:get-path)      # /

       Characterconversion
       The Uri class performs automatically the character conversion in  the  input  uri.  For  example,  the  +
       character  is  replaced by a blank. The % character followed by two hexadecimal values is replaced by the
       corresponding ASCII character. Note that this conversion does now apply to the query string.

       Querystring
       The get-query method returns the query string of the uri. The query string starts after the ?  character.
       The query string is a series of key-pair values separated by the & character.

       const uri (afnix:www:Uri
         "http://www.afnix.org?name=hello&value=world")
       println (uri:get-query) # name=hello&value=world

       The module also provides the UriQuery class that parses the query string and store the result in the form
       of a property list. The query string parse is particularly useful when writing automated scripts.

       # create a query string object
       const qs (afnix:nwg:UriQuery (uri:get-query))
       # get the name value
       qs:get-value "name"

       Managingacgirequest
       Managing  a  cgi request involves primarily the parsing of the requesting uri. The uri generally contains
       the http referrer as well as parameter which are stored in the form of a query string. However, depending
       on the cgi method which can be of type GET or POST, the treatment is somewhat different.

       Checkingtheprotocolversion
       In the presence of a cgi protocol, it is always a good idea to check the protocol version, or at least to
       put an assertion. The protocol version is  normally  CGI/1.1  and  is  stored  in  the  GATEWAY_INTERFACE
       environment variable.

       # check the cgi protocol
       assert "CGI/1.1" (
         afnix:sys:get-env "GATEWAY_INTERFACE")

       Gettingthequerystring
       If  the  request  method  is  GET,  then  the  query  string  is  available  in  the environment variable
       QUERY_STRING. If the request method is POST, the query string is  available  in  the  input  stream.  The
       length  of  the  query  string is given by the CONTENT_LENGTH environment variable. The following example
       illustrates the extraction of the query string.

       # check the cgi protocol
       assert "CGI/.1" (
         afnix:sys:get-env "GATEWAY_INTERFACE")
       # initialize the query string
       const query (afnix:sys:get-env "QUERY_STRING")
       # get the request method
       const rqm (afnix:sys:get-env "REQUEST_METHOD")
       # check for a post request and update the query string
       if (== rqm "POST") {
         # create a buffer from the content length
         const len (
           Integer (afnix:sys:get-env "CONTENT_LENGTH"))
         # get the standard input stream and read content
         const is  (interp:get-input-stream)
         const buf (is:read len)
         # set the query string
         query:= (buf:to-string)
       }

       Parsingthequerystring
       The UriQuery class is designed to parse a cgi query string. Once  the  string  has  been  parsed,  it  is
       possible to perform a query by key since the class operates with a property list.

       const query (
         afnix:www:UriQuery "name=hello&value=world")
       query:length      # 2
       query:get-value "name"  # hello
       query:get-value "value" # world

       The  UriQuery  class  is  the  foundation  to build cgi script. When the library is combined with the web
       application management (wam) service, powerful applications can be built easily.

       Specialfunctions
       Several dedicated functions are available in the library as a  way  to  ease  the  object  manipulations.
       Theses functions operate mostly on uri and files as described below.

       Urifunctions
       Several  functions  are  designed  to  ease the uri manipulation. Most of them operate on the uri name or
       their associated system name. The normalize-uri-name function normalizes a string argument  by  adding  a
       uri  scheme  if  missing in the original string. If the function detects that the name starts with a host
       name, the http scheme is added. If the function detects that the string starts  with  a  path,  the  file
       scheme  is added. otherwise, the name argument is left untouched. The system-uri-name function normalizes
       the string argument by prioritizing the system name. The function attempts to find a file that match  the
       sring argument and eventually build a uri file scheme. If the file is not fond, the normalization process
       occurs with the normalize-uri-name function.

       # normalize a uri name
       trans  unm "http://www.afnix.org"
       assert unm (
         afnix:nwg:normalize-uri-name unm)
       assert unm (
         afnix:nwg:normalize-uri-name "www.afnix.org")
       assert unm (
         afnix:nwg:normalize-uri-name "//www.afnix.org")

       Mimefunctions
       Mime functions are dedicated to easee the mainpulation of media types or mime. A media type is defined by
       a  string  in the form of a type and content value such as text/plain. The mime-value-p predicate returns
       true if a string mime value is a  valid  media  type.  From  a  file  perspective,  the  mime-extension-p
       predicate  returns  true  if  the  string extension has a valid media type associated to it. Finally, the
       extension-to-mime function can be used to get the string mime value associated with a file extension.

       # check a media type
       assert true (afnix:nwg:mime-value-p "text/plain")
       # check the mime extension predicate
       assert true (afnix:nwg:mime-extension-p "txt")
       # check the extension to mime
       assert "text/plain" (
         afnix:nwg:extension-to-mime "txt")

       HTTPtransactionobjects
       The concept of HTTP transactions is defined in RFC 2616. In the client/server approach, a client issues a
       request which is answered with a response. A special case arise when the server is asked to perform  some
       extra  works, such like executing a script. In this case, the answer is called a reply which is formatted
       into a response when the server does its job correctly.  The nature of the HTTP  objects  determines  how
       the  associated stream behaves. With a HTTP request, the object is filled by reading an input stream when
       operating on the server side. On the other hand, the request is filled by  data  when  operating  on  the
       client  side. With a HTTP response, the opposite situation occurs. The HTTP response is filled by reading
       an input stream when operating on the client side and filled by data when operating on the server side.

       HTTPprotocol
       The HttpProto class is a base class designed to handle a HTTP header that is found in both  HTTP  request
       and  response. The class is built around a property list that is filled either by parsing an input stream
       or by processing specific methods. The HttpProto defines also some methods which are often  used  with  a
       HTTP request or response.

       HTTPresponse
       The  HttpResponse class is a class designed to handle a HTTP response. When operating on the client side,
       the response object is built by reading an input stream. When operating on the server side, the  response
       object is built by calling specific methods.

       Creatingaserverresponse
       A  server  response  is  created  by  specifying the response status code. By default, a HTTP response is
       created with the default media type text/html. If the media type needs to be changed, it can be passed as
       the second argument to the response constructor. By default,  the  empty  constructor  creates  an  empty
       constructor with a valid status code.

       #create a valid response
       const hr (afnix:nwg:HttpResponse 200)

       Once  the  server  response  is created, it can be augmented with some headed values. Typically, a server
       will add some information about the response, such like the content length, the modification  time  or  a
       tag. The HttpResponse provides several methods that ease the generation of these header values.

       Creatingaclientresponse
       A  client  response  is created by binding an input stream to a response object. During the construction,
       the input stream is read and the HTTP protocol header is filled. It is also during this  phase  that  the
       status  code  is processed. It is therefore important to ensure that a response object is built correctly
       before attempting to access it.

       # create a client response by stream
       const hr (afnix:nwg:HttpResponse is)

       Readingaclientresponse
       When the response has been created, it is important to check its status  code.  Most  of  the  time,  the
       response  is  valid  and  its content can be read directly. The status-ok-p predicate returns true if the
       status code is valid. In such case, a HTTP stream can be built in order to read the response.

       # check that a response is valid
       if (hr:status-ok-p) {
         # create a http stream
         const rs (afnix:nwg:HttpStream ht is)
         # read the response stream
         while (rs:eos-p) (rs:read)
       }

       Before reading a http stream, it is important to detect and verify the nature of  the  response  content.
       The  media-type-p  predicate  returns  true  if  the  media type is defined and the get-media-type method
       returns the response type in the form of a mime code such like text/html. Eventually, the  character  set
       associated  with the media type can also be detected. The encoding-mode-p predicate and the get-encoding-
       mode method can be used to detect the content encoding mode. However,  it  is  worth  to  note  that  the
       HttpStream  object  is  automatically  sets  with  the proper encoding if it can be found in the response
       header.

       Specialclientresponse
       Certain response can sometime contains special status codes that require a specific  treatment.  This  is
       the  case  when the response corresponds to a http redirection. In this case, the new uri must be fetched
       to get the desired response. The location-p predicate returns true if the response corresponds to a  http
       redirect  and  the get-location method can be used to get the new location uri. If this situation arises,
       it is up to the implementation to decide what to do with the new uri. In most cases, a new  request  will
       be sent to the server.

       Cookieobject
       The  Cookie  object  is a special object that can be used during a http session, to post data to the http
       client. The idea behind cookies is to be able to maintain some state, during the user  session  for  some
       time.  A cookie is a name/value pair and eventually an expiration time. By default, the cookie object are
       defined for one http client session, but this behavior can be changed.

       Managingcookies
       A cookie is created with a name/value pair and eventually an expiration time.  Such  expiration  time  is
       called  the maximum-age and is automatically formatted by the object. With two arguments a session cookie
       is created. With a third argument as an integer, the constructor set the maximum age in seconds.

       # create a cookie with name/value
       const cookie (afnix:nwg:Cookie "cartid" "123456789")

       The cookie implementation follows the recommendation of the RFC-2965 for http state management. The  most
       important point to remember is the interpretation of the maximum age that differs from one cookie version
       to another. With version 1, which is the default, the maximum age is defined relatively in seconds, while
       it  is  absolute  with  version  0.The  maximum age is set either at construction or with the set-max-age
       method. The set-max-age method sets the cookie life time in seconds, in reference to the current time.  A
       negative  value  is  always  reset to -1 and defined a session cookie. A 0 value tells the http client to
       remove the cookie. The set-path method defines the path for which this cookie apply.

       Addingacookie
       Once the cookie is defined, the set-cookie method of the HttpResponse object can be used to  install  the
       cookie. Combined with the write method, the cookie can be send to the http client.

Uri
       The  Uri  class  is  a base object used to parse or build a uniform resource identifier as defined by RFC
       3986. The URI can be built by specifying each component or by parsing a string. When a string is given in
       the constructor, the class parses the string and extract all  components.  The  uri  components  are  the
       scheme,  the  authority, the path, the query and the fragment. The class also takes care of the character
       escaping.

       Predicate

              uri-p

       Inheritance

              Object

       ConstructorsUri(none)
              The Uri constructor creates an empty uri object.

              Uri(String)
              The Uri constructor create a uri object by value. The string argument is the uri to parse  at  the
              object construction.

              Uri(StringStringInteger)
              The  Uri  constructor  create  a uri object by scheme host and port. The first argument is the uri
              scheme. The second argument is the uri host name. The third argument is the uri port. The uri base
              name can be reconstructed from this information.

       Methodsparse->none(String)
              The parse method reset the uri object, parse the string argument and fill the uri object with  the
              result.

              get-scheme->String(none)
              The get-scheme method returns the scheme of the parsed uri object.

              get-authority->String(none)
              The get-authority method returns the authority part of the parsed uri.

              get-path->String(none)
              The get-path method returns the path of the parsed uri.

              get-path-target->String(none)
              The  get-path-target method returns the path target of the parsed uri. The path target is the last
              element of the uri path.

              get-query->String(none)
              The get-query method returns the complete query string of the parsed uri. Note that characters are
              not escaped when getting the string.

              get-fragment->String(none)
              The get-fragment method returns the complete query string of the parsed uri.

              get-base->String(none)
              The get-base method returns the combined uri scheme and authority.

              get-rname->String(none)
              The get-rname method returns the reference uri name with the combined uri  scheme,  authority  and
              path all percent encoded.

              get-hname->String(none)
              The get-hname method returns the combined uri scheme, authority and path.

              get-aname->String(none)
              The  get-aname  method  returns  the almost combined uri name with the scheme, authority, path and
              query.

              add-path->Uri(String)
              The add-path method adds a path to the calling uri and returns a new uri with the new  path  added
              to the old one.

              get-href->Uri(String)
              The  get-href  method returns a new uri by eventually combining the string argument. If the string
              argument correspond to an uri, the corresponding uri is built. Otherwise, the string  argument  is
              considered as a path to be added to the current uri in order to build a new uri.

              get-system-path->String(none)
              The  get-system-path  method returns the system path representation of the uri path. This function
              works only if the scheme if a file scheme.

              get-path-encoded->String(none)
              The get-path-encoded method returns the uri in the encoded form. Normally the get-path removes the
              percent-encoded characters which might not be appropriate with some protocol such  like  the  http
              protocol.  The get-path-encoded returns the original path. Note that getting the path with getpath
              and doing a percent coding might result in a different result since  the  internal  representation
              uses normalized string.

              get-host->String(none)
              The  get-host  method  returns the authority or path host name if any can be found with respect to
              the scheme. With a ftp, http or https scheme, the host is extracted from  the  authority.  With  a
              mailto scheme, the host is extracted from the path.

              get-port->Integer(none)
              The get-port method returns the authority port if any can be found with respect to the scheme.

       UriQuery
       The  UriQuery  class is a simple class that parses a uri query string and build property list. during the
       parsing process, a special transliteration process is done as  specified  by  RFC  3986.  This  class  is
       primarily  used  with  cgi scripts. Note that the string to parse is exactly the one produced by the get-
       query method of the Uri class.

       Predicate

              uri-query-p

       Inheritance

              Plist

       ConstructorsUriQuery(none)
              The UriQuery constructor creates an empty uri query object.

              UriQuery(String)
              The UriQuery constructor create a uri object by value. The string argument is the uri query string
              to parse at the object construction. The query string is  the  one  obtained  from  the  get-query
              method of the Uri class.

       Methodsparse->none(String)
              The parse method reset the uri query object, parses the string argument and fill the property list
              object with the result.

              get-query->String(none)
              The get-query method returns the original query string.

       UriPath
       The  UriPath  class  is  a  class  designed for the management of file system path associated with a uri.
       Typically, this class will be used with a http server or client when an association between a uri  and  a
       file  name needs to be made. The general operation principle is to associate a path with a uri authority.
       The uri path is then concatanated to produce a new path. If the uri path is empty, it can  be  eventually
       replaced by a file name, known as the diretory index in the http terminology.

       Predicate

              uri-path-p

       Inheritance

              Object

       ConstructorsUriPath(none)
              The UriPath constructor creates an empty uri path object.

              UriPath(String)
              The  UriPath  constructor  create  a  uri object by root path. The string argument is the uri root
              path.

              UriPath(StringString)
              The UriPath constructor create a uri object by root and index. The first string  argument  is  the
              uri root path and the second string argument is the directory index path.

              UriPath(StringStringString)
              The  UriPath  constructor  create  a  uri  object  by  root, index and authority. The first string
              argument is the uri root path, the second string argument is the  directory  index  path  and  the
              third argument is the authority.

       Methodsget-root->String(none)
              The get-root method returns the root path.

              get-index->String(none)
              The get-index method returns the index path.

              get-authority->String(none)
              The get-authority method returns the uri authority.

              map-request-uri->String(none)
              The  map-request-uri map a request uri into a system path. The string argument is the request uri.
              The request uri must be an absolute path. The result string is the system path build with the root
              path.

              normalize->String(none)
              The normalize method build a system from a request path. The request path is associated  with  the
              root path and then normalized to produce a complete system path.

       HttpProto
       The  HttpProto  class  is  a  base class that ease the deployment of the http protocol. The base class is
       built with a property list which is used to define the message header. The class also defines  the  write
       methods which are used to write a message either on an output stream or into a buffer.

       Predicate

              http-proto-p

       Inheritance

              Object

       Methodsreset->none(none)
              The reset method resets the http protocol object by clearing the protocol version and header.

              parse->none(none)
              The  parse method parse the input stream bound to the http protocol. In order to operate, an input
              stream must be associated with the protocol object or an exception is raised. After a  stream  has
              been parsed, the protocol version and the header are set.

              write->none(none|OutputStream|Buffer)
              The  write  method  formats  and  writes the http protocol object to an output stream or a buffer.
              Without argument, the default output stream is used. With an  argument,  an  output  stream  or  a
              buffer object can be used.

              header-length->Integer(none)
              The header-length method returns the number of properties in the header.

              header-exists-p->Boolean(String)
              The  header-exists-p  predicate  returns  true  if  the  property exists in the header. The string
              argument is the property name.

              header-set->none(StringLiteral)
              The header-set method sets a new property to the http header. The first argument is  the  property
              name. The second argument is a literal object which is internally converted to a string.

              header-get->Property(Integer)
              The header-get method returns a property object by index.

              header-map->String(String)
              The header-map method returns a property value by name. The string argument is the property name.

              header-find->Property(String)
              The  header-find  method  returns  a  property object by name. The string argument is the property
              name. If the property is not found, the nil object is returned.

              header-lookup->Property(String)
              The header-lookup method returns a property object by name. The string argument  is  the  property
              name. If the property is not found, an exception is raised.

              header-plist->Plist(none)
              The header-plist method returns the header in the form of a property list.

              content-length-p->Boolean(none)
              The  content-length-p  predicate  returns  true  if  the content length is defined in the protocol
              header.

              get-content-length->Integer(none)
              The get-content-length method returns the content length defined in the protocol  header.  If  the
              content length is not defined in the header, the null value is returned.

              media-type-p->Boolean(none)
              The media-type-p predicate returns true if the content type is defined in the protocol header.

              get-media-type->String(none)
              The get-media-type method returns the media type defined in the protocol header. If the media type
              is not defined in the header, the default media type is returned.

              encoding-mode-p->Boolean(none)
              The encoding-mode-p predicate returns true if the encoding mode is defined in the protocol header.

              get-encoding-mode->String(none)
              The  get-encoding-mode  method  returns  the  protocol  encoding mode. If the encoding mode is not
              defined in the protocol header, the default encoding mode is returned.

       HttpRequest
       The HttpRequest class is a base class designed to handle a http request.  The  class  operates  with  the
       protocol  version  1.1  as  defined by RFC 2616. For a server request, the request is built by reading an
       input stream and setting the request command with its  associated  header.  For  a  client  request,  the
       request  is  formatted with a request command and a eventually a uri. In both cases, the header is filled
       automatically depending on the request side.

       Predicate

              http-request-p

       Inheritance

              HttpProto

       ConstructorsHttpRequest(none)
              The HttpRequest constructor creates a default http request. By  default,  the  request  object  is
              built with the GET method and the request uri set to the root value.

              HttpRequest(String)
              The HttpRequest constructor creates a http request object with a specific command. By default, the
              request uri is set to root, except for the OPTIONS method

              HttpRequest(Uri)
              The  HttpRequest  constructor creates a http request object with a uri. The default request method
              is GET.

              HttpRequest(InputStream)
              The HttpRequest constructor creates a http  request  object  with  a  specific  input  stream.  At
              construction, the request header is cleared and the input stream is bound to the object.

              HttpRequest(StringString)
              The  HttpRequest  constructor creates a http request object with a specific method and a uri name.
              The first string argument is the request method to use. The second  string  argument  is  the  uri
              attached to the command. Note that the term uri should be understood as a request uri.

              HttpRequest(StringUri)
              The  HttpRequest  constructor  creates a http request object with a specific method and a uri. The
              first string argument is the request method to use. The second argument is the uri attached to the
              method.

       Methodsset-method->none(String)
              The set-method method sets the request method. This method does not check that the  command  is  a
              valid  HTTP method and thus leaves plenty of room for server development. As a matter of fact, RFC
              2616 does not prohibit the existence of such extension.

              get-method->String(none)
              The get-method method returns the request method string.

              set-uri->none(String)
              The set-uri method sets the request uri. The argument string does not  have  to  be  a  valid  uri
              string  since  some  commands might accept special string such like "*" to indicate all applicable
              uri.

              get-uri->String(none)
              The get-uri method returns the request uri string.

       HttpResponse
       The HttpResponse class is a base class designed to handle a http response. The class  operates  with  the
       protocol  version  1.1 as defined by RFC 2616. For a client response, the response is built by reading an
       input stream and setting the response status code with its associated header. For a server response,  the
       response is formatted with a response status and additional header information. In both cases, the header
       is filled automatically depending on the response side. On the other hand, trying to set some header with
       an input stream bound to the response object might render the response object unusable.

       Predicate

              http-response-p

       Inheritance

              HttpProto

       ConstructorsHttpResponse(none)
              The  HttpResponse constructor creates a default http response object. The response is marked valid
              with a default text/plain media type.

              HttpResponse(Integer)
              The HttpResponse constructor creates a http response object with a status code. The response  code
              is associated with the default text/plain media type.

              HttpResponse(InputStream)
              The  HttpResponse  constructor  creates  a  http  response object with a specific input stream. At
              construction, the response header is cleared and the input stream is bound to the object.

              HttpResponse(IntegerString)
              The HttpResponse constructor creates a http response object with a status code and a  media  type.
              The first argument is the status code. The second argument is the associated media type.

       Methodsset-status-code->none(Integer)
              The set-status-code method sets the response status code.

              get-status-code->Integer(none)
              The get-status-code method returns the response status code.

              map-status-code->String(none)
              The map-status-code method returns a string representation of the response status code.

              status-ok-p->Boolean(none)
              The status-ok-p predicate returns true if the response status code is valid (aka status 200).

              status-error-p->Boolean(none)
              The status-error-p predicate returns true if the response status code is an error code.

              location-p->Boolean(none)
              The  location-p predicate returns true is the response status code indicates that a request should
              be made at another location. The location can be found with the get-location method.

              get-location->String(none)
              The get-location method returns the location uri found in the  response  header.  This  method  is
              equivalent to a header query.

              set-location->none(String)
              The  set-location  method set the redirect location in the response header. The string argument is
              the location uri.

              set-cookie->none(Cookie)
              The set-cookie method sets a cookie object to the http header.  The  cookie  version  is  properly
              handled by the method.

       Cookie
       The Cookie class is a special class designed to handle cookie setting within a http transaction. A cookie
       is  name/value  pair that is set by the server and stored by the http client. Further connection with the
       client will result with the cookie value transmitted by the client to the server. A  cookie  has  various
       parameters  that  controls  its  existence and behavior. The most important one is the cookie maximum age
       that is defined in seconds. A null value tells the client to discard the cookie. A cookie without maximum
       age is valid only during the http client session. A cookie can be added to the HttpReply object with  the
       set-cookie  method. A cookie can be constructed with a name/value pair. An optional third argument is the
       maximum age. The default cookie version is 1 as specified by RFC 2965. With a version 1, the maximum  age
       is interpreted as the number of seconds before the cookie expires. With version 0, the maximum age is the
       absolute time.

       Predicate

              cookie-p

       Inheritance

              Object

       ConstructorsCookie(StringString)
              The  Cookie  constructor creates a cookie with a name value pair. The first argument is the cookie
              name. The second argument is the cookie value.

              Cookie(StringStringInteger)
              The Cookie constructor creates a cookie with a name value  pair  and  a  maximum  age.  The  first
              argument  is  the  cookie name. The second argument is the cookie value. The third argument is the
              cookie maximum age.

       Methodsget-version->Integer(none)
              The get-version method returns the cookie version.

              set-version->none(Integer)
              The set-version method sets the cookie version. The version number can only be 0 or 1.

              get-name->String(none)
              The get-name method returns the cookie name. This is the name store on the http client.

              set-name->none(String)
              The set-name method sets the cookie name. This is the name store on the http client.

              get-value->String(none)
              The get-value method returns the cookie value. This is the value stored on the http client bounded
              by the cookie name.

              set-value->none(String)
              The set-value method sets the cookie value. This is the value store on the http client bounded  by
              the cookie name.

              get-maximum-age->Integer(none)
              The  get-maximum-age  method  returns the cookie maximum age. The default value is -1, that is, no
              maximum age is set and the cookie is valid only for the http client session.

              set-maximum-age->none(Integer)
              The set-maximum-age method sets the cookie maximum age. A negative value is reset to -1. A 0 value
              tells the http client to discard the cookie. A positive value tells the http client to  store  the
              cookie for the remaining seconds.

              get-path->String(none)
              The  get-path method returns the cookie path value. The path determines for which http request the
              cookie is valid.

              set-path->none(String)
              The set-path method sets the cookie path value. The path determines for  which  http  request  the
              cookie is valid.

              get-domain->String(none)
              The get-domain method returns the cookie domain value.

              set-domain->none(String)
              The set-domain method sets the cookie domain value. It is string recommended to use the originator
              domain  name  since  many  http  client  can  reject  cookie  those domain name does not match the
              originator name.

              get-port->Integer(none)
              The get-port method returns the cookie port number.

              set-port->none(Integer)
              The set-port method sets the cookie port number. This value is not used with a cookie version 0.

              get-comment->String(none)
              The get-comment method returns the cookie comment value.

              set-comment->none(String)
              The set-comment method sets the cookie comment value.

              get-comment-url->String(none)
              The get-comment-url method returns the cookie comment url value.

              set-comment-url->none(String)
              The set-comment-url method sets the cookie comment url value. This value is not used  with  cookie
              version 0.

              get-discard->Boolean(none)
              The get-discard method returns the cookie discard flag.

              set-discard->none(Boolean)
              The  set-discard method sets the cookie discard flag. The discard flag the tells the user agent to
              destroy the cookie when it terminates. This value is not used with cookie version 0.

              get-secure->Boolean(none)
              The get-secure method returns the cookie secure flag.

              set-secure->none(Boolean)
              The set-secure method sets the cookie secure flag. When a cookie is secured, it is  only  returned
              by the http client if a connection has been secured (i.e use https).

              to-string->String(none)
              The  to-string  method  returns a string formatted for the http reply header. Normally this method
              should not be called since the set-cookie method of the httpReply takes care of such thing.

       Session
       The Session class is a class that defines a session to be associated  with  a  transaction.  The  session
       object  is designed to be persistent so that its data information can be retreived at any time. A session
       object has also the particularity to have a limited lifetime. A session object is created by name with an
       identifier. The session object is designed to hold a variety of parameters that are suitable for both the
       authentication and the session lifetime. A  session  is  primarily  defined  by  name  with  an  optional
       information string. The session is generally associated an authentication visa which contains the session
       identity. The visa provides a secure mechanism compatible with a single sign on session. A session key is
       automatically generated when the session is created. Such key is used to generate a session hash id which
       can  be  used  as  a cookie value. The cookie name is also stored in the session object. When a cookie is
       generated, the session hash name is combined with the session hash id for the cookie production.

       Predicate

              session-p

       Inheritance

              Taggable

       ConstructorsSession(String)
              The Session constructor creates a session by name. The string argument is the session name.

              Session(StringString)
              The Session constructor creates a session with a name and  a  user.  The  first  argument  is  the
              session name. The second argument is the session information..

              Session(StringStringInteger)
              The  Session  constructor  creates  a  session  with  a  name, a user and a maximum age. The first
              argument is the session name. The second argument is the session informartion. The third  argument
              is the session maximum age expressed in seconds.

       Methodsexpire-p->Boolean(none)
              The expire-p predicate returns true if the session has expired.

              set-hash-id->none(String)
              The  set-hash-id  method  sets the session hash identifier. The session hash id must be unique and
              secured enough so that the session name cannot be derived from it.

              get-hash-id->String(none)
              The get-hash-id method returns the session hash identifier.

              set-path->none(String)
              The set-path method sets the session path.

              get-path->String(none)
              The get-path method returns the session path.

              get-max-age->Integer(none)
              The get-max-age method returns the session maximum age.

              set-max-age->none(Integer)
              The set-max-age method sets the session maximum age. The maximum age  is  an  integer  in  seconds
              relative to the current time. If the maximum age is set to 0, the session is closed.

              get-remaining-time->Integer(none)
              The get-remaining-time method returns the remaining valid session time.

              get-expire-time->Integer(none)
              The  get-expire-time method returns the session expiration time in seconds. The expiration time is
              an absolute time.

              set-expire-time->none(Integer)
              The set-expire-time method sets the session expiration time. The expiration time  is  an  absolute
              time in seconds.

              get-creation-time->Integer(none)
              The  get-creation-time  method returns the session creation time. The creation time is an absolute
              time in seconds.

              get-modification-time->Integer(none)
              The get-modification-time method returns the session creation time. The modification  time  is  an
              absolute time in seconds.

              get-cookie->Cookie(name)
              The  get-cookie  method bakes a session cookie. The string argument is the cookie name those value
              is the session hash id value.

              close->Cookie(name)
              The close method close a session by reseting the session maximum age to 0. The  method  returns  a
              cookie  that  can  be  used  for  closing the session on the peer side. The string argument is the
              cookie name those value is the session hash id value.

       Functionsmime-extension-p->Boolean(String)
              The mime-extension-p predicates returns true if a media type  extension  -  mime  extension  -  is
              defined. Most of the time, media type extension can be seen as a file extension.

              mime-value-p->Boolean(String)
              The mime-value-p predicates returns true if a media type - mime value - is defined.

              extension-to-mime->String(String[Boolean])
              The  extension-to-mime  function  converts  a media type extension into a media type. In the first
              form, without a second argument, if the media type extension  does  not  exist,  an  exception  is
              raised. In the second form, with the second argument set to true, if the media type extension does
              not exist, the default media type is returned. If the flag is set to false, an exception is raised
              like the first form.

              string-uri-p->Boolean(String)
              The string-uri-p predicates returns true if the string argument is a uri.

              normalize-uri-name->String(String)
              The  normalize-uri-name  function normalizes the string argument by adding a uri scheme if missing
              in the original string. If the function detects that the name starts with a host name, the  "http"
              scheme  is added. If the function detects that the string starts with a path, the "file" scheme is
              added. otherwise, the name argument is left untouched.

              system-uri-name->String(String)
              The system-uri-name function normalizes the string argument by prioritizing the system  name.  The
              function  attempts  to  find a file that match the string argument and eventually build a uri file
              scheme. If the file is not fond, the normalization  process  occurs  with  the  normalize-uri-name
              function.

              path-uri-name->String(String)
              The path-uri-name function normalizes the string argument by extracting a path associated with the
              uri  string.  If  the string is a valid uri string, the path is the uri path component. If the uri
              path is empty, it is normalized to a /. If the string argument is not a uri string, the string  is
              assumed to be a partial uri and both query and fragment parts are removed if present.

              normalize-uri-host->String(String)
              The  normalize-uri-host  function  normalizes  the string argument uri host name. This function is
              useful with certain class of host representation which uses extra characters.

              normalize-uri-port->String(String)
              The normalize-uri-port function normalizes the string argument uri port value.  This  function  is
              useful with certain class of host representation which uses extra characters.

AFNIX Module                                          AFNIX                                               nwg(3)